Wireless telecommunications services are provided to customers via one of two payment methods—prepaid and postpaid. Postpaid accounts are designed such that if the customer exceeds the number of voice minutes, data capacity, text messages, or other services allocated to their account in a billing cycle, the postpaid customer will be charged for the excess services at the end of the billing cycle. Often times, the customer is unaware of the overage and is requested to pay an unexpected amount at the end of the billing cycle.
Services, such as AT&T's Rollover® service, aim to eliminate overages by accumulating unused minutes at the end of each billing cycle for use in future billing cycles. For example, if a customer uses 900 minutes of a 1000 minute service plan during a billing cycle, the remaining 100 unused minutes are added to the customer's total available Rollover® minutes. If the customer exceeds their 1000 minute service plan during a future billing cycle, the customer's Rollover® account is debited the overage amount of minutes instead of the customer being charged overage fees for the excess minutes. Minutes in a customer's Rollover®account are typically set to expire after a predetermined time, such as every year.
Prepaid customers typically purchase a credit for a predetermined number of voice minutes prior to receiving wireless voice service. By purchasing credit in advance of use on a wireless service network, a customer can access a wireless service network without contractual obligation and an ongoing bill (e.g., re-occurring bill). A customer may then use the wireless network until the expiration of the purchased, or prepaid, credit.